Polishing apparatus



insulation to remove tends to dry'or b'ecome'sticky,

'* er shoes, irrespective of Patented Nov. 1, 1938 UNITED PST-AT ES PATENT OFFICE 2,135,200 POLISHING APPARATUS Beauford' H. Reeves, Pine Orchard, Conm, assignorto Ro'ckloestos Products Corporation, a corporation of Massachusetts Application May 6, 1936,

1 10 Claims.

This invention relates to the manufacture of insulated wiresand cables and more particularly wires and cables insulated with a fibrous material like asbestos.

In the manufacture of insulated-wires and cables'in which the insulation consists in whole or in part of a fibrous material like asbestos it is I customary to initially apply the fibrous material in the formof a loose layer surrounding the metallic conductor. The so-covered conductor is then customarily passed through aliquid'bathof an appropriate flame-proofing compound to impregnate the layer of fibrous insulating material with the compound, and-subsequently the im- 'pregnated layer of insulation is compressed and smoothed. Centrifugal devices of-various types have heretofore been employed for effecting this compressing and smoothing operation. Such centrifugal devices-operate in direct contact with the looselyapplied and still wet layer of fibrous excess impregnating compound and to compact and condense the layer of insulation into a firm smooth concentric wall about the conductor. Similar centrifugal devices are also employed as-"smoothingburnishers on dry insulated wire for improving the appearance thereof.

' The heretofore customary types of centrifugalcompressing and smoothing devices *have possessed certain disadvantages which may be briefly summarized as follows:

1 1. Lack of self-centering when used on wires of different diameters. This is especially true when the device is operated with its axis horizontal, due to the effect of gravity. 2.- Lack of adjustability to control the pressure and minimum distance between the polisher shoes.

-3. Location ofthe centrifugal mechanism in the same plane as the polishing shoes, which results in throwing off-impregnating compound parts where it into bearings and other moving thus rendering such parts inoperative.

4. Difficulty in cleaning to their inaccessibility.

the polisher shoes due The present invention contemplatesan im- 7 proved centrifugal compressing "and smoothing apparatus in which the'aforementioned disadvantages are overcome. Thus, in the apparatus ofthe invention the polisher shoes are so connected to the centrifugal mechanism that the latter transmits pressure uniformly to the polishthe size of the insulated 'wire and of the operating :positionoi-the ap- Serial No. 78,292

'paratus.

tion the force of thepolisher minimum distance therebetween is susceptible of convenient predetermined control. Again; in the apparatus of the invention the centrifugal mech-; anism is longitudinally spaced from the zone of compression and smoothing and no difficulty is experienced by the accumulation of partially dry or sticky impregnating compounds in the operat- .ing parts. These and other advantages of the apparatus of the invention willbe better understood from the following description taken in conjunction with the accompanying drawings in which Fig. 1 is a plan view of the apparatus, 5

Fig. 2 is another view of the apparatus taken at right angles to that of Fig. 1,

' Fig. 3 is a sectional elevation on the section line 3-3 of Fig. 1, and

Fig. 4 is a sectional elevation on the section line 4-4 of Fig. 1.

Referring to the drawings, the apparatus comprises a hollow rotatable spindle 5 adapted to be rotated (by means not shown) at suitable speeds. A cylindrical hub 5 is adapted to be slipped on and off the end of the spindle 5 and in operation is secured to the spindle byset screws 1. A pair of levers 8 are pivoted intermediate their ends to diametrically opposite bosses 9 on the hub ii.

' The levers are symmetrically positioned on. op-

. posite sides of the longitudinal axis of the spin- ,dle.

A compressing and polishing device Hi (hereinafter referred to as a polisher shoe) is p-iv-,

otally mounted at one end of eachof the levers 8. A fly-ball weight H is pivotally attached to the other yoked end of each lever 8. The inner faces of the polisher shoes til may be flat, cylindrical or V-shaped to provide the most efficient polishing contact. The shape will vary with the character of insulation to be compressed or polished. That portion of each lever 8 between its polisher shoe to and its pivot in thebossfi is humped or outwardly bent (8') to provide a point of discharge for any impregnating compound creeping along this portion of the lever from the polisher shoe.

The weights H are operatively connected by a parallel linkage consisting of four yoke-ended links IZ-pivoted together at their yoke ends in the shape of a diamond. Diametrically opposite pivots of the parallellinkage are pivotally connected to the weights llyand the other diametrically opposite pivots of the linkage'are pivotedto plungers i3. The plungers:l3 areposi-aifili Nov. 1, 1938. B. H. REEVES 2,135,200

POLISHING APPARATUS Filed May 6, 1936 2 Sheets-Sheet 2 a f I 1 w I V2: HI i m" l' I f I! I:

v INVENTOR ATTORNEYS Patented Nov. 1, 1938 UNITED STATES PATENT OFFICE POLISHING APPARATUS Beauford H. Reeves,

Pine Orchard, Conm, assignorto Ro'ckbestos Products Corporation, a cori 10 Claims.

' customary to initially apply the 'fibrous material in the form of a loose layer surrounding the metallic conductor. The so-covered conductor is then customarily passed through a liquid bath-of an appropriate flame-proofing compound to impregnate the layer of fibrous insulating material with the compound, andsubsequently the impregnated layer of insulation is compressed and smoothed. Centrifugal devices of various types have heretofore been employed for effecting this compressing and smoothing operation Such centrifugal devicesoperate in direct contact with the loosely applied and still wet layer of fibrous insulation to remove excess impregnating compound and to compact and condense the layer of insulation into afirm smooth concentric wall about the conductor. Similar centrifugal devices are also employed assmoothing burnishers on dry insulated wire for improving the appearance thereof.

The heretofore customary types of centrifugal compressing and smoothing devices have possessed certain disadvantages which may be briefly summarized as follows:

1. Lack of self-centering when used on wires of different diameters. This is especially true when the device is operated with its axis horizontal, due to the effect of gravity.

- 2. Lack of adjustability to control the pressure and minimum distance between the polisher shoes.

- 3-. Location ofthe centrifugal mechanism in the same plane as the polishing shoes, which results in throwing off "impregnating compound into bearings and other moving parts where it' tends to dry or become sticky, thus rendering such parts inoperative.

4. Dimculty in cleaning the polisher shoes due to their inaccessibility.

The present invention contemplates-an 'improved centrifugal compressing and smoothing apparatus in which the aforementioned disadvantages are overcome. of the invention the polisher shoes are so connected to the centrifugal-mechanism that the latter transmits pressure uniformly to the polisher shoes, irrespective of the size of the insulated wire and of the operating 'positionof the ap- Thus, in theapparatus paratus. Also, in theapparatus of the invention the force of the-polisher shoes and the minimum distance therebetween is susceptible of convenient predetermined control. Again; in the apparatus of the invention the centrifugal mech-' anism is longitudinally spaced from the zone of compression and smoothing and no difficulty is experienced by the accumulation of partially dry or sticky impregnating compounds in the operat ing parts. These and other advantages of the apparatus of the invention will be better understood from the following description taken in conjunction with the accompanying drawings in which Fig. 1 is a plan view of the apparatus, 17

Fig. 2 is another view of the apparatus taken at right angles to that of Fig. 1,

' Fig. 3 is a sectional elevation on the section line 3-3 of Fig. 1, and

Fig. 4 is a sectional elevation on the section line 44 of Fig. 1.

Referring to the drawings, the apparatus comprises a hollow rotatable spindle 5 adapted to be rotated (by means not shown) at suitable speeds. A cylindrical hub t is adapted to be slipped on and off the end of the spindle 5 and in operation is secured to the spindle by'set screws 1. A pair of levers 8 are pivoted intermediate their ends to diametrically opposite bosses 9 on the hub 6. The levers are symmetrically positioned on opu posite sides of the longitudinal axis of the spindle.

A cempressing and polishing device Hi (hereinafter referred to as a polisher shoe) is pivctally mounted at one end of each of the levers 8. A fly-ball weight H is pivotally attached to the other yoked end of each lever 8. The inner faces of the polisher shoes it may be flat, cylindrical or V-shaped to provide the most efficient polishing contact. The shape will vary with the character of insulation to be compressed or polished. That portion of each lever 8 between its polisher shoe l9 and its pivot in the boss 9 is humped or outwardly bent (8) to provide a point of discharge for any impregnating compound creeping along this portion of the lever from the polisher shoe.

The weights H are operatively connected by a parallel linkage consisting of four yoke-ended links l2 pivoted together at their yoke ends in the shape of a diamond. Diametrically opposite pivots of the parallel-linkage are pivotally connected to the weights ll, and the other diametrically opposite pivots of the linkage are pivotedto plungers i3.- The. plungers l3 are p0Si-sn55 from further inward movement.

In the operation of the apparatus of the invention, the hub 6 is mounted on and secured to the revolving spindle 5 of the compressing and polishing machine. The spindle may be in a horizontal 'or vertical position depending upon the type of the machine. The spindle is tubular to permit the axial passage therethrough of the wire l6 to be compressed and polished. The polisher shoes iii. are so supported that they can swing in the axial plane of the wire and thus insure uniformity of contact and pressure throughout their length. The spindle 5 is rotated at a suitable speed to bring the polishing shoes into operation through the effect of centrifugal force'on the weights H.

. Appropriate means ,are provided topull the insulated wire longitudinally and axially through the tubular spindle and between the polisher shoes 'at the proper linear speed in' relation to the revolving speed of the spindle get the desired finish. V

Polisher shoes of different sizes and fly-balls of varying weights to suit'wires of different types may be used and are easily interchanged. The complete mechanism can be removed as a unit and replaced by another. All parts are assembled in operating relation on the central hub B and are readily accessible for repair, renewal and cleaning. I

The advantages of the improved compressing and smoothing apparatus of the inventionmay be briefly summarized as follows:

'1. The parallel linkage connecting the levers 8 (through the weights H) and the plungers l3 necessitates equal radial movement of the Weights (and polisher shoes) regardless of the position in which the apparatus operates or of the size of the wire being processed.

'2. The closing of the polisher shoesto apply and polisher shoes to pressure to'the insulation of the wire being processed is controlled by the adjusting screw H5 in one of the plungers l3 by the fact that the head of the screw is larger than the hole inthe plunger guide i so that when the head of the screw seats against theend of the guide, "the plunger is restrained from further inward movement. This prevents (through the connection of this plunger with the parallel linkage) the weights H from further outward movement, and, therefore, limits the minimum distance between the polisher shoes. 3; By the bell-crank construction of the levers '8,-the entire centrifugal operating mechanism is removed from the zone of actual polishing and applying impregnating compound, and no difliculty is experienced due to'accumulation' of partially dry or sticky compound in the operating parts. I 1

4. The humped shape of the levers 8 between the polisher shoes l0 and the hub 6 insures that any impregnating compound which might creep up the levers from the polishing zone will be thrown off the levers by centrifugal force before it can reach the bearings or pivots of the levers in the bosses 9 of the hub 6.

'5. The pressure of the polisher shoes increases gradually from zero to a maximum as the machine is started up and decreases correspondingly as the machine is stopped. This prevents twisting of the insulated wire and consequent objectionable disturbance of the insulation. 7

6. Cleaning the polisher shoes is very easy since they are accessible-from all sides and are easily removed if necessary.

I claim: I

1. In an apparatus for compressing and smoothing insulation about a metallic conductor, the combination with a rotatable spindle of a hub adapted to be secured to said spindle, a pair of levers pivoted intermediate their ends to said hub and symmetrically positioned on opposite sides of the longitudinal axis of said spindle, each of said levers carrying a compressing device at one end thereof and a weight at the other end thereof, and

parallel linkage operatively connecting said a cooperating pair of compressing devices, apair' of centrifugally responsive weights operatively connected to said compressing devices and longitudinally spaced therefrom, and parallel linkage comprising a plurality of interconnected links operatively connecting said weights whereby pressure due to the centrifugal action of said weights is transmitted uniformly to each compressing device. 7

4. In an apparatus of the character described for processing insulation about a metallic con-v ductor, the combination with a rotatable spindle of a pair of cooperating"compressing devices longitudinal axis of said spindle, a pair. of centrifugally. responsive weights symmetrically positioned on opposite sides of the longitudinal axis symmetrically positioned on opposite sides of the of said spindle and longitudinally spaced from said compressing devices, means operatively connecting said compressing devices to said weights and to said spindle, and linkage means operatively connecting said weights toone another whereby pressure due to the centrifugal action of said Weights is transmitted uniformly toeach' compressing device. r

5. In an apparatus of the character described for processing insulation about a metallic conductor, the combination with a cooperating pair of compressing devices of a pair' of centrifugally.

responsive Weights operatively connected to said compressing devices and longitudinally spaced therefrom, parallel linkage operatively connect-f ing said weights, and means comprising a plurality of pivoted members cooperating with said linkage for limiting outward movement of said weights due to centrifugal action. r

6. In an apparatus for, compressing and smoothing insulation about a metallic conductor, 7

the combination with a rotatable spindle of a hub adapted to be secured to said spindle, a pair of levers pivoted intermediate their ends to'saidhub and symmetrically positioned on opposite sides of the longitudinal axis of said spindle, a compressing device attached at one end of'each lever, the portion of said levers between said 'hub and said compressing devices being outwardly humped to provide a centrifugal discharge point for liquid removed from the insulation, and a centrifugal mechanism operatively connected to the other ends of said levers.

'7. In an apparatus for compressing and smoothing insulation about a metallic conductor, the combination with a rotatable spindle of a hub adapted to be secured to said spindle, a pair of levers symmetrically positioned on opposite sides of the longitudinal axis of said spindle, each of said levers being pivoted intermediate its ends to said hub, a compressing device operatively attached to one end of each lever, said compressing devices being symmetrically positioned on opposite sides of the longitudinal axis of said spindle and longitudinally spaced from said hub, a Weight carried by the other end of each lever, and parallel linkage operatively connecting said weights.

8. In an apparatus for compressing and smoothing insulation about a metallic conductor, the combination with a rotatable hollow spindle of a hub adapted to be secured to said spindle, a pair of levers symmetrically positioned on opposite sides of the longitudinal axis of said spindle, each of said levers being pivoted intermediate its ends to said hub, a compressing device pivoted to one end of each lever, said compressing devices being symmetrically positioned on opposite sides of the longitudinal axis of said spindle and longitudinally spaced from said hub, a weight carried by the other end of each lever, parallel linkage surrounding said spindle and having one pair of its diametrically opposite pivots attached to said weights respectively, a plunger attached to each of the other diametrically opposite pivots of said linkage, a. guide for each of said plungers attached to said hub, and means cooperating with one of said plungers for limiting its inward movement in response to the force imparted thereto by the centrifugal action of said Weights.

9. In an apparatus of the character described for processing insulation about a metallic conductor, the combination with a rotatable spindle of a plurality of compressing devices, a centrifugally actuated weight connected to each compressing device, a linkage interconnecting said weights, and means operatively connected tosaid linkage for limiting the outward movement of said Weights.

10. In an apparatus for compressing and smoothing insulation about a metallic conductor, the combination with a rotatable spindle of a hub adapted to be secured to said spindle, a pair of levers pivoted intermediate their ends to said hub, each of said levers having a compressing device attached to one end thereof and a weight on the other end thereof, and a parallelogram linkage connecting the weights, said levers extending in the longitudinal direction of the ap- 

